Membrane Transport

molecules move across the plasma membrane by crossing the lipid bilayer directly, rather than by using a transport protein.

molecules move across the plasma membrane against their concentration gradient.

a vesicle inside the cell fuses with the plasma membrane and releases its contents outside the cell.

the plasma membrane forms a pocket that pinches inward, forming a vesicle that contains material from outside the cell.

A molecule moves down its concentration gradient using a transport protein in the plasma membrane. This is an example of

endocytosis.

active transport.

facilitated diffusion.

diffusion.

exocytosis.

Water crosses the plasma membrane

through active transport.

against its concentration gradient.

through facilitated diffusion or diffusion.

using a process that requires energy from the cell.

through cotransport.

The sodium-potassium pump uses energy from ATP to move sodium ions out of the cell, and potassium ions into the cell. This is an example of

diffusion.

passive transport.

active transport.

exocytosis.

facilitated diffusion.

The plasma membrane forms a pocket that pinches inward, forming a vesicle that contains material from outside the cell. This describes the process of

passive transport.

active transport.

exocytosis.

diffusion.

endocytosis.

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